Base Converter
Convert fractional or integer values between Binary, Octal, Decimal, Hexadecimal, and any custom base up to 62. Type in any field to sync all bases instantly.
Multi-Base Synchronizer
What Does the Base Converter Do?
The Base Converter converts numbers between four common numeral systems: Binary (base 2), Octal (base 8), Decimal (base 10), and Hexadecimal (base 16). Enter a number in any base and see the equivalent value in all four systems instantly — no manual calculation required.
Numeral base conversion is a foundational skill in computing, networking, and programming. Every number a computer processes is ultimately stored and processed in binary. Decimal is how humans naturally count. Hexadecimal is used extensively in web colors, memory addresses, debugging, and cryptography. Octal appears in Unix file permission codes (like 755 or 644).
Whether you're a developer debugging a value in memory, a student learning computer science, or an engineer converting IP subnet masks, this tool handles the conversion instantly in your browser — with zero data sent to any server.
All calculations run locally in JavaScript. There are no round-trips, no latency, and no privacy risk. Just fast, accurate numeral conversions.
How It Works
- 1 Select Input Base: Type your input into any system field — Binary, Octal, Decimal, Hexadecimal, Base 36, Base 62, or choose a Custom Base.
- 2 Type Values: The converter automatically parses values as you type. If you enter invalid characters for that base (like '9' in binary), it displays an error immediately.
- 3 Synchronize Instantly: All other base values sync immediately without page reloads. Fractional/floating point inputs are supported (e.g. 42.25).
- 4 Copy Results: Click the copy button next to any row to send that converted value to your clipboard.
Key Features
Instant Conversion
All base conversions display simultaneously as you type. No need to click Convert — the outputs update in real time.
Fractional Base Support
Converts both integers and fractional values (decimal points) up to base 62, retaining floating-point precision.
One-Click Copy
Copy any output value to your clipboard instantly. No selecting, no dragging — just click the copy icon next to the result you need.
100% Private
All conversions run locally in JavaScript. Your numbers never leave your browser — no server, no logging, no tracking.
The Four Number Systems: Quick Reference
| Base System | Base | Valid Digits | Decimal 255 = | Common Use |
|---|---|---|---|---|
| Binary | 2 | 0, 1 | 11111111 | CPU operations, data storage, logic gates |
| Octal | 8 | 0–7 | 377 | Unix file permissions (chmod 755), legacy systems |
| Decimal | 10 | 0–9 | 255 | Human-readable numbers, everyday math |
| Hexadecimal | 16 | 0–9, A–F | FF | Web colors (#FF5733), memory addresses, cryptography |
Common Use Cases
Programming & Debugging
Convert memory addresses, flags, and bitmasks between hex and decimal when reading logs, disassembler output, or network packets.
Web Color Codes
Convert RGB decimal values (255, 87, 51) to hexadecimal (#FF5733) for CSS, HTML, or design tools that use either format.
Unix File Permissions
Convert between octal permission codes (755, 644) and their binary equivalents (rwxr-xr-x) when setting chmod permissions.
Computer Science Study
Practice binary addition, hex multiplication, or two's complement conversions — instantly verify your answers with the converter.
Tips for Working with Number Bases
- Remember Binary is Powers of 2: Binary digits represent powers of 2 (1, 2, 4, 8, 16…). The rightmost bit is 2⁰ = 1, the next is 2¹ = 2, and so on.
- Hex = 4 Bits: One hex digit always represents exactly 4 binary digits (a nibble). FF = 11111111. This makes hex a compact shorthand for binary.
- Octal = 3 Bits: One octal digit represents exactly 3 binary digits. Octal 7 = binary 111. Very useful for Unix permissions.
- Use Prefix Notation: In code, prefix 0b for binary (0b1010), 0o for octal (0o17), and 0x for hexadecimal (0xFF). This prevents ambiguity.
- Verify Color Codes: RGB colors are often listed as 0–255 decimal. Convert to hex to get CSS color codes: R=255, G=87, B=51 → #FF5733.
- Check Your Input Base: A common mistake is entering a hex value but selecting decimal as input base. Always verify which base selector is active before converting.
Frequently Asked Questions
Base conversion is the process of expressing the same numeric value using a different counting system. The number 255 in decimal equals FF in hexadecimal, 11111111 in binary, and 377 in octal — all four represent the same quantity.
Hexadecimal is compact — one hex digit represents 4 bits. This makes it a natural shorthand for binary values. Memory addresses, color codes, cryptographic hashes, and machine instructions are all commonly expressed in hex.
"Base 2" means the number system uses only 2 distinct digits: 0 and 1. Each position in the number represents a power of 2. Binary is base 2. Decimal is base 10. Hex is base 16.
Multiply each digit by 16 raised to its position (right to left, starting at 0). For example, 2A hex: A=10 × 16⁰ + 2 × 16¹ = 10 + 32 = 42 decimal. Or just use this tool and get the answer instantly.
The tool uses JavaScript's native number parsing, which is accurate up to 2⁵³ − 1 (Number.MAX_SAFE_INTEGER). For very large integers, consider using BigInt-based tools instead.
Octal is used primarily in Unix/Linux file permissions. The chmod 755 command sets permissions using octal: 7=rwx, 5=r-x. Each octal digit maps directly to 3 binary digits representing read, write, and execute bits.
Yes. Once the page is loaded, all conversions run in JavaScript in your browser. You can disconnect from the internet and continue converting numbers without interruption.
100% free. No account, no subscription, no watermarks, no limits. Convert as many numbers as you need at no cost.
Why Choose GetGetLocalTools?
Maximum Privacy
Every tool runs in your browser. No uploads, no data retention, no tracking. Your data stays on your device, always.
Instant Results
No server round-trips. All four base conversions calculate simultaneously in real time using native JavaScript.
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Works Everywhere
Fully responsive across desktop, tablet, and mobile. Works on Chrome, Firefox, Edge, and Safari without plugins.
Privacy Promise
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